The Shift Gig finished earlier than expected. Can I send the worker home early?

Only pay workers for the time they spent working.

You are only required to pay the Worker for the actual time they spent working your Shift, so it is completely acceptable to send them home if they finish early. Both Workers and the Requesters can terminate the Shift at any time for any reason. 

If a Worker completes your task in less time than expected, or circumstances prevent the Shift from continuing, you can end the Shift. The Worker payment is always based on the agreed upon Bid Rate and Worker's start and end time, not the Shift’s scheduled start and end time. 
In addition, once the Shift is completed, Requesters have the option to edit Worker timesheets to ensure the correct start time, end time, and any unpaid breaks are accounted for. Once you are satisfied with the worker timesheet you can submit it to finalize the worker’s payment.